Rather than starting with no item, and backing so early, I would suggest getting Sapphire Crystal to start (with or without potions). The 200 mana it gives helps to patch up Niv's mana usage before backing, and upgrades into Tear or Catalyst. I find that a full start of Sapphire Crystal and potions will keep me going until I have well over 550 gold, and I don't have to back and lose farm while the enemy mid pushes.